The DDM4, Also Known as The Lite Rail III, Is The Third Generation Of Lite Rail From Daniel Defense. The Improved Design enhances The RailíS Structural Integrity, improves Functionality, Ergonomics, Aesthetics And Ease Of Installation To The Weapon System Without Compromising Its Best-Known attributes, One Of Which Being The Lightest Rail System On The Market. Enhanced features Include a machined One-Piece Design, replacing The Previous Two-Piece Welded Design Of The 1St Generation Lite Rail, And uses Daniel Defense's patented Bolt-Up System. The DDM4 Requires Only 4 Bolts Instead Of 6 And Has tabs That Aid In Alignment To The Upper Receiver During Installation. Front And Rear Sling Swivel Attachment Points Are Integrated Into Both The Left And Right Side Rails And Are Designed To Limit The SwivelíS Rotation preventing Twists And tangles In Slings.